Anybody who follows my Instagram page will know that I spent five hours in a paediatric outpatient department today. It was a pretty torturous experience; the background noise of babies grumbling, the lethargy of tired parents losing their cool, and tears as a cheeky boy snatched a rice cake from an unsuspecting baby girl. At times it felt as if we would never make it out of there, especially when they informed us that they’d lost my daughter’s notes. But as we had little choice about being there when it's something as important as our child's health we grit our teeth and got on with it, coming up with every unimaginable way to prevent the inevitable meltdown. We didn’t avoid it, but still, we got through it.

When I signed with Headline back in 2015 it was a huge moment for me. The idea of having a book deal had at one point seemed like an unattainable dream, back when I was writing without an agent and collecting rejection slips with each passing day. But I kept going with a quiet optimism, and a belief that one day I would succeed in finding somebody who believed in my novel as much as I did. Still, when I received the email to say my book had sold I was speechless. But not only because MY SISTER had sold to a great publisher, but because they had also decided to buy a book I was yet to write.

Now that kind of faith in my ability to provide something that was not only attractive to the publisher but salable to an ever fluid market brought with it a set of new anxieties for me. I was immensely proud, but also scared; I had never written a novel to order before. I had always done my own thing. But with the editing process for MY SISTER complete, I had to start my second, contracted, psychological thriller.

It began easily enough; unplanned and uncontrolled. That was how every book started back then. I got an idea and ran with it. But when you are writing to meet contractual deadlines, and a synopsis that you provided, writing with such freedom is unsustainable. Because going off on every random tangent without a destination is not without consequence. Book two grew not only in size but complexity. But as it grew it began to veer further and further from its brief. The synopsis seemed less relevant the further I progressed, and a meeting with my agent left me with the impression that I didn’t understand my own book; by then I was a few drafts and 110,000 words in. That's about nine months of work that had stopped making sense.

And the hardest thing to admit as my submission deadline approached, was that I wasn't really happy with where I had ended up. Quite simply, book two had grown into a monster. It was much like today’s hospital visit - there was a whole lot of fuss, with people running around all over the place, but when it came to the plot, much like my daughter's notes, it was lost.

I wrestled with it a bit longer but with the pressure of deadlines looming right around the corner I submitted it to my agent. I knew I needed some guidance, but the hardest thing to admit to both myself and her, was that if I'd have been searching for representation at that time I wouldn't have submitted that manuscript. I knew it was far from ready. Obviously my editor knew that too and we arranged a meeting, and I planned a trip to the UK. And as I boarded an early flight to London on a crisp December day in 2016, knowing that about seven hours later I would have to explain how I planned to resolve the issues with my mess of a manuscript, I was struck by an overwhelming thought; I needed to write another book. Plenty of great writers will tell you not to give up on something because it got hard, but I knew drastic action was the only way forward. So instead of working on my edits during the flight I wrote a new synopsis. It was a new book, but one that without the first draft of book two might never have come to mind. And the gamble worked. My editor loved it. All I had to do was go back to the drawing board, start from chapter one. And oh yes, could I do it in just a few months? I decided I could at least try.

With a lot of time at my desk I got the book written in the two months proposed. I slipped away from life at the weekends and worked early and until it was late. And after submitting to my agent I got the email I was waiting for: she loved the book. Fortunately my editor did too.

In the year it took me to rework the mess of the first draft into the final manuscript a lot has changed. I bought a house while it was still being built, managed to move in. I lost a father to cancer, and spent six unforgettable weeks sitting at his bedside. And recently, just after I got my copy edits back I too became a mother when we adopted our beautiful baby girl. In this last year book two has grown, and I have grown with it. It has been the most challenging book I have ever written. It has been one of the hardest years I think I have lived. But last Friday I submitted my copy edits to my editor. That means we are nearly there. It means that book two is nearly finished. It means, just like today, with a little bit of grit, I got through it.